These small molecule inhibitors target TEA domain (TEAD) proteins, with the potential to treat diseases with altered Hippo signaling, such as Hepatocellular Carcinoma (HCC) and Hepatoblastoma (HB). The Hippo signaling pathway is vital to organ growth control, stem cell function, regeneration, and tumor suppression. Inactivation of the Hippo pathway leads to the dephosphorylation of YAP/TAZ proteins and their translocation to the nucleus, where they interact with TEAD transcription factors, activating the transcription and translation of genes involved in cell proliferation and survival, as well as leading to carcinogenesis. A broad range of carcinomas, including HCC, present a high rate of dysregulation of the Hippo pathway. For this reason, targeting the YAP-TEAD complex, essential for regulating the Hippo pathway, is an attractive strategy for treating these cancers.
HCC is one of the most common malignant cancers, with increasing incidence and mortality in recent years in the United States. The disease progression in patients involves severe liver inflammation and fibrosis that correlate with the deregulation of various signaling pathways and genetic aberrations. Patients with advanced HCC have a poor prognosis. Although there are several systemic therapies for the treatment of HCC, drug resistance, and undesired toxicities remain a hurdle. Only 12 percent of patients have a one-year survival with current treatments, highlighting the urgent need to develop new and more effective therapeutic approaches for treating HCC. Hepatoblastoma (HB) is a rare malignant tumor of the liver in the pediatric population. It is found in 90% of cases before the age of three. 32 YAP1S127A withdrawal significantly regresses hepatoblastoma, implicating YAP1 as a therapeutic target for HB.33. While a novel T-cell therapy, ET140203 (ARTEMIS), has an orphan drug designation by the FDA for treating pediatric HB.34, no small-molecule drug is available for HB. Preoperative or postoperative chemotherapy remains the primary treatment and HB remains a deadly disease with unmet medical needs.
Researchers at the University of Florida have developed small molecule YAP-TEAD inhibitors for treating diseases with altered Hippo signaling. By targeting and blocking the activity of the YAP-TEAD transcriptional complex, these compounds are promising therapeutics for the treatment of HCC and HB while carrying low toxicity.
YAP-TEAD small molecule inhibitors for the treatment of diseases with altered Hippo signaling, such as HCC and HB
These small molecules target and inhibit TEAD proteins for treating diseases with altered Hippo signaling, such as Hepatocellular Carcinoma (HCC) and Hepatoblastoma (HB). Upon dysfunctional Hippo pathway regulation, YAP proteins translocate to the cell nucleus and interact with TEAD transcriptional factors to drive oncogenic transcriptional programs vital for cancer cell growth, survival, and epithelial-mesenchymal transition. These compounds covalently bind to the core pocket of TEAD through a cysteine residue on the protein, impairing the protein-protein interaction with YAP and depicting a potential therapeutic strategy for treating HCC and HB. In in vitro studies, the compounds show potent inhibition of YAP-related downstream genes and HCC and HB cell line growth. In in vivo studies, they significantly inhibit tumor growth in the xenograft and HB mouse models with no apparent toxicities.